Dolphins RB Kory Sheets out for the season with torn Achilles

Update (1:04 p.m.): An NFL source has confirmed to colleague Ben Volin that Kory Sheets tore his Achilles tendon in his right leg and is out for the season.

Sheets was running back what proved to be the final return of a kickoff return drill when the injury occurred. He was at about the 40-yard-line and just beginning to slow down when the ball came flying from his grasp and he crashed to the ground holding his right leg.

It’s a tough blow for the Dolphins, who were considering Sheets as their fourth running back and, more importantly, kickoff return specialist.

“I liked what he was doing with the ball under his arm during the course of practices,” said head coach Tony Sparano, who said after practice that he didn’t know the extent of Sheets’ injury. “Pretty explosive guy.”

While concerned teammates – most notably fellow running back Ronnie Brown – gathered around, trainers hovered over Sheets for several minutes before being helped up. He needed the assistance of two trainers to reach the sideline, before assistant trainer Troy Maurer escorted him to the locker room, his right leg still dragging behind him.

Sheets, 25, who was signed last Oct. 14 off the practice squad of the San Francisco 49ers, had routinely been the first man up in kick return drills and seemed to be battling rookie Nolan Carroll for the starting job. Backup running back Tristan Davis has also been involved.

Sparano has said he liked what he’d seen of Sheets and Sheets, realizing his running back reps will be limited behind Brown and Ricky Williams, was anxious to get the job, going so far as to say he’d talked to the coaches about it after arriving last season.

“If I can get a spot like that,” he said, “you never know what can happen.”

The morning workout was the start of the third two-a-day since camp opened last Friday. Another workout that will be open to the public will be held at 8 tonight. We’ll update this after Tony Sparano speaks at 12:30.

Sheets is the second Dolphin to go down with a season-ending Achilles injury, joining defensive end Phillip Merling. He’s also the second Dolphin to be lost for the season in a matter of three days — rookie linebacker A.J. Edds tore his ACL on Monday night.

Sheets seemed to be in good spirits Wednesday afternoon. From his Twitter account:

“Don’t worry ppl I’m ok this is just a bump n the road I’ll be back faster n better then ever. Thanks for the Love. GO FINS!!!”